This invention relates generally to refrigeration systems and, more particularly, to condensers for refrigerators.
Refrigeration systems typically include a compressor coupled to a condenser so that a compressed refrigerant flows to the condenser. See, for example, U.S. Pat. No. 5,711,159. A condenser fan circulates air over a surface of the condenser to cool the compressed refrigerant and is powered by a condenser fan motor.
Condenser surfaces for refrigerators are typically of tube and wire construction in which a refrigerant tube, or condenser coil, including a plurality of U-shaped segments is attached to a plurality of substantially parallel wires. In one type of condenser, a plurality of tube and wire members are placed in parallel rows underneath a refrigerator cabinet in an air flow path extending from a front of the refrigerator cabinet. See, for example, U.S. Pat. No. 5,592,829 However, this requires an increased distance between the refrigerator cabinet and a floor to provide adequate air access to the condenser surfaces, and, more importantly, suffers from reduced efficiency due to unevenly distributed airflow across the condenser surfaces and airflow parallel to the refrigerant tubes and/or wires. Air flowing through a relatively small air path through a lower front of the refrigerator produces relatively high air velocity and pressure drop of the air, which reduces an airflow rate across the condenser, increases noise, and reduces condenser efficiency. The reduced condenser efficiency results either in a decreased energy efficiency of the refrigerator or an increased cost in the condenser because of extra coil that is required to obtain a required heat transfer to the air.
Rectangular or cube shaped condensers have been developed to reduce the condenser volume and conserve space. See, for example. U.S. Pat. No. 5,685,166. However, these condensers also suffer efficiency losses due to uneven airflow over the condenser surfaces and airflow parallel to the condenser surfaces. Thus, extra coil is often required to achieve a desired heat transfer to the air. Also, a considerable number of U-shaped elbows with small radiuses are required to fabricate the rectangular condenser shape, which increases condenser cost and decreases condenser reliability.
Accordingly, it would be desirable to provide a refrigerator condenser that more effectively transfers heat to the air, promotes even air flow across the condenser surface, reduces the need for extra condenser coil, and avoids the need for U-shaped elbows of small radius that compromise condenser reliability and increases condenser cost.